package jdbc;

import java.sql.Connection;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;

public class JDBCDemo6 {
    public static void main(String[] args) {

        try (
                Connection connection = DBUtil.getConnection()
        ) {
            Statement statement = connection.createStatement();
            String sql = "select count(*) count " +
                         "from class c " +
                         "join student s on c.id = s.class_id " +
                         "where c.name = '1年级1班' ";
            ResultSet rs = statement.executeQuery(sql);
            while (rs.next()) {
                int count = rs.getInt("count");
                System.out.println("人数:"+count);
            }

        } catch (SQLException e) {
            e.printStackTrace();
        }


    }
}
